


Hunters and shadowhunters

by I_can_not_function



Category: Mortal Instruments Series - Cassandra Clare, Supernatural
Genre: Cross Over, I Don't Even Know, Multi, am i doing this right, first fanfic
Language: English
Status: In-Progress
Published: 2014-06-11
Updated: 2015-07-09
Packaged: 2018-02-04 07:38:26
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 4
Words: 3,430
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1771030
Author URL: https://archiveofourown.org/users/I_can_not_function/pseuds/I_can_not_function
Summary: <blockquote class="userstuff">
              <p>The Winchesters found a vampire nest in Brooklyn, New York when they got there they heard two kids talking about the supernatural like its normal so they decide to trail them not knowing where it would get them</p>
            </blockquote>





	1. 1

**Author's Note:**

> This is my first fanfic so sorry if it's rubbish. I just thought there were not enough supernatural/TMI crossovers and thought I would give it a try so here it is. Sorry for any typos  
> I do not own supernatural or the mortal instruments

Sam and Dean stepped out of the impala looking up to the old wreck of the hotel dumort. Earlier Sam had tracked a vampire nest in Brooklyn, New York. The address had lead them here.  
'Come on, Sammy. Let get this over and done with.'  
'Are you sure about this dean? I mean as far as I can tell is a massive nest, don't you think we should call on some other hunters for back up?' Sam asked as he stepped out of the car waking towards the trunk.  
'Nah it's fine. I'm sure we can handle it.' Once they had grabbed their weapons, a machete each and a couple of shots filled with dead mans blood in their pistols (and the weapons they never let go of), they walked toward the back of the hotel looking for a way in.  
They were pushing bins around noisily while looking for a way in, until the heard voices they stopped and listened.   
-  
'You really didn't need to come along, clary. I know how much you hate it here.'  
'No simon, it's cool. Plus you hate it much more than anybody else. We will just grab the blood and go back to the institute. We can make it quick.'  
'Yeah but the only vamp that actually does not hate me is Raphael and I need to be really careful they might not like it if i bring you too.'  
-  
Sam and Dean stuck their heads around the corner to see where the voices were coming from. They came from two teenagers, both looked around 16, one skinny and average height boy with brown hair (who must be simon) and one girl a little shorter than the other with fiery red hair(most likely called Clary).  
They went into the hotel through the front door.  
'How on earth do a pair of teenagers know about vamps and why would they need blood?' Dean asked.   
'I dunno they might be hunter kids but I have no idea about the blood.' Sam and Dean decided to find out so they waited until they came out and followed.  
-  
'Thank for coming, Clary'  
'Any time, Simon. Got what you need?' She asked and she took out her phone typing something.  
'Yeah. Who you texting?'  
'Oh I'm just telling Jace were on our way back.' Simon rolled his eyes to that.  
'What?' Asked Clary.   
'Nothing' he answered but still smiled like an idiot.  
-  
The institute turned out to be an old abandoned church of some sort. The bothers shared a confused look but carried on following as discretely as possible.  
The teenagers entered the church and shut the doors behind them. Sam and Dean followed up the steps and just as they were about to open the door they were attacked from behind and were knocked out by strong blows to the head.  
-  
'So that's what you were texting Jace!' Simon said to clary as she helped Isabelle Jace and Alec carry the men into the lift as he held their weapons.   
'What do you think I was texting him?' Clary asked out of breath.  
'I don't know this is you and Jace we are talking about.' Both clary and have shot him an evil glare. Simon stopped talking after that.  
Sam woke up with an aching headache and a very hungry stomach. He opened his eyes quickly, remembering that he was knocked out. He quickly observed the surroundings until his eyes landed on a boy with brown hair and the bluest eyes he had ever seen. The boy looked up from his book and saw Sam awake he quickly rushed out the door. Sam looked down to find himself zip tied to a chair he then tried to shake about but found his chair attached to another on which sat Dean.   
'Dean!' Sam whispered, 'Dean, get up!'  
Dan groaned and pealed open his eyes then shook violently as he remembered what happened.  
'Dude where are we, all I remember is going up those steps and nothing.'  
'Same here, man' Sam answered.  
Dean was halfway through another groan as 4 teenagers entered the room all at once. They didn't even hear their footsteps out side the door before they came in. Sam recognised the boy who was in the room when he woke up and the girl they were trailing yesterday, Clary as he remembered it. The other two were not familiar. One was a tall muscular boy with blonde hair and golden eyes that stared right into Sam and Dean as he walked in. The other was a tall and pretty girl with long dark brown hair and dark brown eyes. They all had strange marks tattooed into their skin.   
'Rise and shine sleeping beauties!' Said the blond one with a sneer.  
'Good morning,' replied Dean. 'I would like to speak with you parents, did they not tell you it's rude to knock out random strangers?'  
'Did yours not tell you it's weird to follow random strangers?'  
Dean opened his mouth then shut it.  
'Thats enough Jace,' Clary said to the blonde boy.'who are you and why were you following me and Simon?'  
'Shouldn't we just call maryse?' Said the other boy.'oh come on Alec,' said the girl with brown hair.'we might as well ask them and if is nothing we can scare them off ourselves!'   
'Fine,' replied Alec, 'but if anything happens it'd be your fault not mine, okay izzy?'  
'Fine!'  
'As I was saying...,' carried on clary.'who are you and why did you follow me?'  
Sam and Dean looked at each other. Then Sam shrugged and answered.  
'My name is Sam Winchester and this is my brother dean,' pointing towards him, 'and as far as we can tell you know about vamps right?'  
'Yeah,' replied the girl called izzy, 'but how do mundies like you know so much, I mean you obviously have the sight but you have no runes so you aren't shadowhunters then what are you?'


	2. Chapter 2

CHAPTER 2

Sam looked over to Dean who took out a slow breath and looked back at Sam.  
'go on then Sammy.'  
'We are hunters,' answered Sam,' I guess you guys already know a lot about the supernatural so yeah we hunt vampires, as you might have guessed werewolves and all that crap.'  
'Wait so you are mundanes who hunt things that go bump in the night without runes or seraph blades and no training. Tell me more,' sneered Jace.  
'Wait, so how do you kill them without any seraph blades?' Said clary quickly.  
'Well that depends you see, for vampires you chop of heads and for demons I use my demon blade and you know different things.' Answered Dean, 'we have answered you questions now answer ours what the hell is a shadowhunter?'  
'A shadowhunter or as we are also known as nephillim are half angel half human created to keep the mundies safe from demons as for vampires and werewolves we only get them when they are being naughty.' Blurted out Jace.  
'Jace!' Alec exclaimed,'what is it with you and telling people everything! First clary now them, maryse will not be happy when she finds out and more importantly the clave!'  
'Clave?' Asked Sam innocently.  
'Basically like our government.'  
'Oh,' said Sam and Dean together.  
'Wait so how many of you shadowhunters are there?' Asked Dean.  
'Lots we have institutes all over the world and our homeland Idris.' Answered Isabelle.  
'Isabelle!' Said Alec appalled. 'Thats it I'm calling..'  
'Who?' said the shadowhunter boys at the same time.  
'You can't call maryse because she would murder us all don't even consider you dad I mean there is clarys mum but she would just tell yours so who are you gonna call?'  
'I know what Alec is thinking.' Said izzy giggling.'somebody tall slim and really sparkly!'  
'Who?' Said Clary and Jace at the same time.   
'Er hello I think they forgot about us.' Said dean in the background.  
'Shut up mundie' snapped Jace.'Alec who?'  
'Why would I call him izzy and it's not like I have his number or something.' Said Alec blushing slightly.  
'Oh yes you do!' Said Isabelle waving his phone in front of his face. Alec blushed even more,'give that back' said Alec grabbing out for his phone. 'How did you get his number?' Asked clary.  
'He gave it to me,' he mumbled  
'What?' Asked Jace.  
'Last time we saw him when you needed that stuff for the cure he asked me to call him, again and I said how can I call you when I don't have you number he said good point and gave me his number.'  
'Alec. The warlock. Really.' Said Jace slowly .  
'Warlock?' Asked Dean and Sam at the same time who had been sitting there listening the whole time.  
'Yeah the high warlock of Brooklyn.' Said Jace dramatically. 'Why didn't you tell me Alec?'  
'Can we do this later.'  
'Yeah later go on and call sparkles and put the phone on speaker I wanna hear whys he says'  
'Wa..'  
'Just call him!'  
Alec took out his phone it didn't take him long to find Magnus' contact since he didn't have many at all. He took a deep breath in and pressed call.  
'Hey Alec, baby. Finally decided you could not resist?' Said Magnus as he picked up the phone.  
'Shut up Magnus.' Answered Alec blushing even deeper that before only to look around him to see everybody was amused except Jace who looked disgusted. 'We need you help we have a little problem down at the institute.'  
Magnus sighed loudly though the phone,'you really know how to get a guys hopes up don't you Alec? I'll be right there' he said right before he hung up.   
The wait for Magnus was really awkward for everybody but more for Alec. What a way to come out to Jace, Alec thought to himself, good one.  
Magnus let himself in as usual to find izzy waiting for him in the hall out side the room where Sam and Dean were.  
'This way Magnus' said Isabelle as she lead him in.  
He looked around the room until his eyes found Alec 'hey babe' he said to Alec 'we need to arrange a date sometime okay but for now how can I help you?'  
Alec, who by then was blushing really hard pointed towards Sam and Dean. Jace, who had been staring daggers at Magnus just snapped out of his daze. How could he not know? How could he not notice or why didn't Alec tell him?  
'They are our problem' he announced'  
'Hey if you just let us go we can poof out of your existence!' Spoke Dean for the first time in what felt like ages.  
'We can't do that I'm sorry' said Isabelle.  
'Who are they?'asked Magnus  
'I am Sam Winchester and this is my brother dean' answered Sam.  
Something crossed Magnus' eyes at that point like had heard the name before. He took In a deep breath and then exhaled.'THE Sam and Dean. The hunters?'  
'What?'asked Alec Jace izzy and clary at the same time.  
'Magnus how do you know they basically only just told us' said clary.  
'Im way older than a lot of people and you don't think I ever came across hunters? Mundies who don't know shadowhunters exist and think they are the only people trying to keep the world working.'  
'Well i think me and Sammy are done here just untie us and we will be on our way'  
'No' snapped Magnus and Alec at the same time.  
'Well Sammy u think it's time we gout out the big guns don't you' said Dean smiling  
'Big guns' asked clary in a quiet voice.   
'Oh the angel of The Lord castiel we require assistance so get your feathery ass down here.' Announced dean loudly. Everybody looked at him puzzled except for Sam who sat there like he was waiting for something.  
Then there was a loud flapping sound that sounded a lot like wings they turned to find a man with brown hair wearing a trench coat . 'My name is Castiel and I am an angel of The Lord.'

**Notes for the Chapter:**

> As I said before I have no idea what I'm doing I'm just writing what I think is right


	3. Chapter 3

**Summary for the Chapter:**

> The hunters need help with a demon who better to help then the shadowhunters?

An odd silence passed over the room. And then a burst of laughter escaped from Jace. 'An angel?' He laughed 'I've seen one and he certainly did not look like an accountant!' Clary nodded thoughtfully.   
Magnus sighed 'Castiel, of course if you know the story of Sam and dean you know cass. How nice to meet you!' Magnus extended his hand for Castiel. He looked to sam and dean before shaking it hesitantly 'Magnus bane, high warlock of Brooklyn. '  
'Uh Cass a little hand here?' Deans voice cut into his thoughts. 'Oh of course' he answered as he clicked his fingers. Sam and dean got up and stretched. 'Wait what?' Isabelle spoke. 'Somebody please explain what's going on'   
'I Castiel angel of the Lord this is Sam and Dean as I am sure you know and we should get leaving' spoke cass.   
'Leaving?no you need to explain what makes you an angel?'  
'A lot has happened in heaven since you met my brother the system is not so neat so there are a few of us strolling around. Mostly my fault and the fact that we can't find God but' Castiel breathes, 'Sam and Dean I think these nephilin would be able to help you hunt Lucus'  
'Help? we don't need help! Especially not from a bunch of teenagers and an overly sparkly warlock!' Dean sniggered and Sam nodded in agreement. Magnus stopped Jace before he could object.   
'You have been hunting this demon for a week, you need help! Now I have to get back to heaven so let them help you!' And without warning disappeared with a loud flapping noise. 'What was that?' Asked Isabelle. Sam passed Dean a look and the ran. Or they tried 'uh uh' said the warlock as he held them in place from where he was standing across the room 'I would like to hear about this "Lucus" creature' Sam sighed and turned to the warlock 'he is a demon we have been hunting down for a while and we still haven't found him'   
'That doesn't happen to be the rogue demon going around recently does it?' says Isabelle looking towards Alec 'well the name does ring a bell, Magnus?' A massive grin passed over Magnus' face 'This is going to be fun!' He waved his long arm towards the doors 'to the library!'  
>>>>>>>  
Sam looked up in awe to the stacks of books in the large collaboration on shelves in front of him. 'Oh great a book nerd' sighed Jace dramatically as he slouched onto one of the sofas. 'So what is this demon you are looking for called again?' Asked Alec. 'Well actually it so a greater demon and it is called Lucus' Dean answered. 'Okay let's get searching' he spoke as he disappeared into The walls of knowledge.

**Notes for the Chapter:**

> I am so sorry this took so long to update I have been so bust it's crazy. Thank you for reading. Kudos and comments are welcome please tell me whatever you think! Cheers!


	4. Chapter 4

**Summary for the Chapter:**

> Shadowhunter find out that they missed the apocalypse and the hunters find that they don't know as much as they thought

It had been 3 hours and they still had not found a trace of this 'Lucus.' Dean felt himself dosing off while flicking through a weakly bound, handwritten book. 'you kids don't happen to know where your parents keep their beer do you?' he asked hopefully. Jace laughed as he lifted his head from the book he was lying on, 'unfortunately they recently moved their stash for the 45th time.'

'you know what this calls for right?' announced Isabelle standing up. 'yeah, why not? lets go' Clary replied as she stretched. 'What are you doing? we are supposed to be looking for Lucus' Dean snapped.

'we're not going to be doing much when we're half asleep, plus we can get you something better than beer.' retorted the blond boy who he had come to know as Jace.

'they're right Dean, we might as well.' Sam finally spoke, rubbing the sleep out of his eyes. Dean sighed, 'Alright, where are we going then?' jace smirked, 'thats for us to know an.....'

'We are going to Taki's' she snapped, cutting him off. 'Excuse him' Alec said as he burst in, 'he can be a little bit of a drama queen.'

'finally!' Isabelle exclaimed, 'where have you been?'

'in my room' he paused, blushing slightly, 'napping'

'napping?' asked Isabelle shouted just as Magnus burst through the door. 'did you miss me?' Isabelle sighed 'enough chatter. get your arses out of here!' everybody flowed out of the library and made their way to Taki's.

on the way to said diner, Magnus explained of what he knew about the hunters. Sam was impressed about how much he knew about their lives, he knew about things from Lilith to the apocalypse, only missing the odd detail which dean corrected. Sam stopped outside the door above of which was large neon sign labelling the diner Taki's.

'wait so you are saying that we missed the apocalypse, how?' clary asked as she stepped through the door and walked towards a booth where sat a pale teenager who Sam and Dean instantly recalled as Simon. she greeted him with a hug, she was swiftly followed by Isabelle who greeted him with a peck on the lips, 'hey babe'

'urgh, who invited teeth' jace snarled. he was shot a death glare from clary.

'i did,' answered Isabelle, sliding into the booth.

'teeth?' dean asked while slowly reaching for the blade that was tucked into his underwear.

'don't even think about getting that knife out from your pants,' alec shot, ' we knew it was there but nobody wanted to reach in and get it, now sit down.' everybody shuffled into the booths an awkward silence passed over the group. Sam decided sticking his face in the menu was a good option.

'alcohol effused lambs blood?' Sam spluttered. Magnus sighed, 'see unlike you hunters, these people have just the slightest bit more decency to only attack downworders like us,' he indicated himself and simon, 'when we actually do something bad so we can also enjoy simple services like this diner here.'

'okay we told you our story now its your turn to tell us yours. what is the clave? and how do you kill vamps without chopping off their heads?' Dean asked, obviously trying to hide his confusion. jace laughed as simon joked, 'your not planning on hurting me are you?' Sam shook his head but dean just smirked which earned him multiple death glares. 

'Lucky for you, no. Just would like a few answers is all,' he spoke. 'Well you see, We have these things called seraf blade which we use to kill basically everything but unfortunately for you,' issy explained eyeing sam and Dean, ' only shadowhunters can use them' sam perked up at the new information. 'Well since we can't use them could I see one.' Isabelle glanced towards Jace who nodded his head before reaching into her jacket and pulling out a blade and handing it to sam. To sam looked a little like the demon blade except not as many of the symbols. 'Nice' Dean nodded, 'next question, did you get permission from your parents before getting those tattoos?' He quized as he observed the ink that covered jace's arm. Alec and Isabelle had also his ones just like them. 'They are called runes' Alec spoke. He looked to his side to see Magnus staring at him (he had been doing it a while) who only responded by winking which caused Alec to turns bright shade of red as he continued to explain, 'we draw them an using a Steele and they...' 

'Basically like little power-ups!' Simon interrupted. 'Now I'm getting a little hungry, can we order now?' Everybody sounded in agreement and Jace called the waitress who he called Kelie. It was clear they the clary girl did not like her but their suspicions were confirmed when the waitress shot jace a flirtatious smile as she walked over. 

'Hey guys what can I get you today? I'm guessing the usual?' Everybody nodes in turn except for Sam and Dean, 'and what could I get for the plus ones to the party?' She directed at them. They both ordered fries and Burgers along with some basic beers. 

'So how many of these seraf blades do you have.' Jace thought for a second before answering, 'absolutely no idea, the iron sisters can make more I guess.' 

'So you guys have like an endless supply?' Dean asked shocked. 'But only you guys can use them?'

'Wait,' Sam realised ,'is there any way that humans can become shadowhunters?'

**Notes for the Chapter:**

> Sorry for taking ridiculously long to upload. Thanks for reading! Ps shout out to my bestie Lottie for reminding me to update!   
> Find me on tumblr!: midnighturtle.tumblr.com  
> Pps I have definately spelt stuff wrong so I and so sorry for that!


End file.
